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81.
82.
在水溶液条件下以六缺位的[H2P2W12O48)]12-和Eu髥为反应前躯体得到了1个新的多金属氧酸盐化合物[Eu3(H2O)17(α2-HP2W17O61)].5H2O(1),对其进行了元素分析、红外光谱、热重、荧光等表征,并用X-射线单晶衍射测定了它的晶体结构。化合物1含有双支撑的多阴离子簇[{Eu(H2O)7}2{Eu(H2O)3(α2-P2W17)}2]8-,并进一步通过Eu髥连接形成了延c轴方向的一维链。室温条件下的荧光光谱研究表明:化合物1显示了强的红光发射。 相似文献
83.
WANG Zhi-xin HOU Yi HAN Wei WANG Kai-chen GUO Bao-feng LIU Ying CHANG Xi-hua WANG Wei-hua NA Wan-li KONG Xiang-bo ZHAO Xu ZHANG Ling 《高等学校化学研究》2011,27(1):94-98
Renal cell carcinoma is the most common cancer of the kidney, and resistant to traditional therapies. The aim of this study is to investigate the effects of hydroxyapatite nanoparticles on human renal cell carcinoma 786-0 cells. Cell proliferation was assessed with an 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide(MTT) staining kit. The apoptosis assay was assessed with an FITC Annexin V Apoptosis Detection Kit. Caspase-3 and caspase-12 were detected by immunocytochemical staining and semi-qua... 相似文献
84.
Telomerization of tetrafluoroethylene (TFE) with methanol in the presence of a free-radical initiator such as α, α′-azoisobutyronitrile
(AIBN) has been carried out. The product composition was related to kinetic equations involving the chaintransfer coefficients
and the concentration of telomeric fluoroalkanols obtained. 相似文献
85.
O. I. Kotov A. V. Khlybov L. B. Liokumovich S. I. Markov A. V. Medvedev V. A. Rukavishnikov A. I. Borovkov D. V. Shevchenko 《Technical Physics》2006,51(11):1494-1499
It is shown that a lateral pressure applied to a circular single-mode optical waveguide changes the phase difference between two orthogonally polarized modes and thereby modulates the polarization state of light (elastooptic effect). The efficiency of polarization modulation is characterized by a strain-to-phase difference conversion factor as applied to polarization modes of the fiber. An expression relating the phase difference between the modes and the displacement of squeezing plates is obtained and checked in real experiments and numerically. The efficiency of conversion of lateral pressure to phase difference between the polarization modes is shown to be fairly high, on the order of 104 rad/(μm m). 相似文献
86.
V. O. Golub V. V. Kotov Yu. A. Podyelets A. N. Pogorely 《Hyperfine Interactions》1990,59(1-4):293-296
Additional spin-ocho signale from quadrupole nuclei with I=7/2 (Co59 nuclei in Co and Fe−Co thin films) were investigated. It has been shown, that the time dependence of the additional ocho
signals, arising at the time moments 2nς reflect quadrupole interaction inhomogenety. 相似文献
87.
HAI QING LIU LI NA ZHANG AKIRA TAKARAGI TAKEAKI MIYAMOTO 《Cellulose (London, England)》1997,4(4):321-327
The effect of substituent distribution on the water solubility of O-methylcellulose (MC) was re-examined to elucidate the
lower limit of the degree of substitution (DS) in water-soluble MC. To this end, a series of 2,3-MCs which are regioselectively
substituted at the C-2 and C-3 hydroxyl groups were prepared by homogeneous methylation. It was found that the lower limit
for the DS value of water-soluble 2,3-MC was almost the same as that for MCs having even distributions of substituents along
the cellulose chain as well as in the anhydroglucose units.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
88.
89.
V. T. Baranov S. Bellucci V. M. Biryukov G. I. Britvich C. Balasubramanian V. Guidi G. Giannini V. N. Zapolsky V. I. Kotov A. E. Kushnirenko V. A. Maisheev G. Martinelli E. Milan V. A. Pikalov V. I. Terekhov U. Uggerhoj V. N. Chepegin Yu. A. Chesnokov 《JETP Letters》2005,82(9):562-564
Radiation emitted by positrons moving in a periodically deformed crystal has been experimentally observed for the first time. Radiation spectra have been measured in a wide energy range. Experimental evidence has been obtained for an undulator peak in a radiation spectrum, which is qualitatively consistent with calculations. Crystalline undulators ensure an equivalent magnetic field of 1000 T and a period in the submillimeter range and can therefore be used to generate x-ray and gamma radiation that is a hundred times harder than radiation in usual undulators. 相似文献
90.
V. M. Pankov V. L. Prokhin Yu. G. Shkurkin B. A. Yakovlev A. S. Glyanenko Yu. D. Kotov V. Yu. Kovalen' 《Radiophysics and Quantum Electronics》1996,39(11-12):1002-1005
This paper describes the main parameters of an instrument for X-ray flux measurement and solar flare and preflare spectrum registration. The nontraditional CdTe semiconductor detector was space qualified and has sensitivity 0.5 cm2, energy region 3–30 keV, and energy resolutions ~ 1.3 keV for 5.9 keV and ~ 10% for 22.1 keV. 相似文献